Synchronizing attachment for phonographs



1,642,702 Sept- 20 1927 F. H. sTRoM SYNGHRONIZING ATTACHMENT FOR PHONOGRAPHS Filed April 18 1927 2 Sheets-Sheet 2 27A 27B /OR /OIJ 0% TTQRQIEY 'Patented sept. 20,1927. .1,642,302

UNITED STATES PATENT OFFICE..

FREDERIC H. sTnom-or sT. PAUnnINNEsoTa.

sYNcEEoNTzING aTTAciimENT ron rnonocaar application niea'apru is, 19er. serial 110.1841394. y

My invention relates to a device for proerredtype of switch operated by' the said viding continuous, uninterrupted musical acswitch throwing arm, about as on line 3*-3 companiment to motion picture films, by 1n Fig. 2. means of phonograph records, as required by-A Fig. 4 isa schematic wiring diagram of 00 6 a cue sheet, chart, guide or other means for the motor' control means. determining particularly appropriate musi- Fig. 5 is an electrical wiring diagram of a ca'l themes to be. played at certain cues, single synchronizing volume control as used titles, scenes `or actions in said motion in the' use of my device.

picture. Fig. 6 is'a wiring diagram involving inde- 65 10 A-urther object is to provide musical acpendent volumevcontrol and synchronizin eompaniment on one record selection or secmeans, this figure being a modification o? tion of music for an approximate given or Fig. 5. l

predetermined length of-factio'n time. Referring to the, drawings by reference (Action time is here used and undernumerals, I will first describe the mechanical stood to be the length of time necessary to and electrical means of my device which opshow or project a serieso scenes or actions, erate the motors, andl later the `electrical independent of a fixed mathematical relameans of synchronizing control, the lattertionship as between projecting a given num- 1n a preferred form particularly in Fig. 5, ber of feet or and a given number of and a modified form in Fig. 6. 75 seconds; vor as independent and distinct For a thorough understanding of my defrom a fixed period of time in which the revice, it is4 first required that an electric lationship between the number Aof `feet of phonoaph is provided having two turnfilm shown per sec'ond` is' and must be de- 'tables and R, and a motor for each said pendent upon the length and period of time table, as LM and RM for a left and a right '25 necessar to reproduce the musical measures turntable. 15B is a disc type record on the or soun waves in the record; or as distinct Vtable and 15L is a record on table L.

' andindependent from the perfectsynchro- 10 is an electric pick-up including the nization of film and recorded music; its fixed reproducing needle 10N, each said pick-up time relationship made obviously necessary being on the free end of one of the hori- 3" in order to maintain proper musical pitch. zontally oscillatable tone arms 16B or 16L The object of my device is to maintain a lof any suitable form and each said arm 16 certain amount of flexibility or independence pivoted at 17 rearwardly of the turntables,` of the speed of the projection machine; of the two wires from each pick-up 10 being broken film, or cut outs due to censorcarried inside 'tone arm tothe volume` 00 ship) then at the moment of the showing or and synchronizing control which will he. projection of the above mentioned cue, inafter be mor e full described;

' scene oraction, fade out the preceding My device provides the proper music for sectionl'of music and fade in the succeedan entire photoplay, parts or themes being ing selectionwithout any audible break be#A previously recorded 'inv a predetermined ro.- 95

40 tween the sai-d sections or selections o tation on a plurality of disc records with music; this being done by a manually op- Zserial numbers or letters and such records erated electric synchronizing and volume as are not in use on the machine to be withcontrol device as hereinafter fully set forth in reach-of the operator-and exchanged as and illustrated'in the accompanying drawneeded and indicated by the chart; Such 100 ingsl in which: f chart is not illustrated, it being sucient to Fig. 1 is a plan view of an electrically opstate that the progressive' musical numbers erated phonograph wi li two tone arms'haw are recorded on the records, the chart merely ing electric pick-ups and showing lone in indicating the serial. number of the record playing osition on arecord, and the other which shouldibe played from one part of the l10F in nonaying position, adjacent the. other photoplay to another redetermined part of record. v the pla For examp e, anoperator may be Fig. 2 is an enlarged sectional elevation directe by the chartto play record as 15L, about as at line 2-2 in Fig. 1, and showin from its starting oint f oi" approximately particularly the'switchfthrowmg arm 11'0 twominutes.' Thee artmay call for achange' 110 the'tone arm in operative position.v of music at-a `point inthe piotoplay .whic

Fig. 3 is a detail sectional view o f a' prerequires certain music to played. Y e

electric pick-up B, is placed at the outer edge on record B, the V-switch 14R throws the circuit on for motor RM, which in turn drives the turntable R. As this record is in full operation there is no music from thls pick-up 'unit until the synchronizing convin from wall through wire 23, back to trol 18 is turned fromv position 18L asindicated by arrow 19 to 18B. As this control is moved around slow, the .music on' record 15L fades away, the music on record 15E comes in gradually and there is no break in' the music. The blending in and out of, the two strains of music is one of the objects of my invention.

, he V-switch'14 has an arm 12R which is moved. by' the switch throwing arm 11 to position 11A, which closes the circuit between 14R and 13R,which current is fed plug 20v through wire 21, through wire 22, through motor RM,

plug 20 immediately starting motor RM.

In the position thatthe tone arm 1 6L is' playing (as in Fig..1), the switch 14L has a closedA circuit from plug 20 through wire 2l'and 24 through switch 14L, through arm 14Al to contact 13L, wire 25, to motor LM, thence through wire 26 and 23 back to the wall plug 20.

18B.` and 18L decreases. The current which -which tends toA munie an the- V-switch is thrown 4 atin vthrough Ywire 33 to electric pick-.u through wire 34, to the terminal 35, t

ance 18C, through". synchronizing control 18A, through the wire 37, through terminal 38, through wire 39 back to circuit 27B- oi transformer 27.

YllVhen the 4synchronizing `control 18A is `moved as from 18A to position 18F` or thereabout, the resistance between 18B and 18F is increased'and the resistance between goes through wire 33 decreases as current is mcreasing in, wire 41 through the electric pick-up lOL, through wire 42, tothe ter- .minal 43, wire 44,- to terminal 18L, and the resistance 18C to the, synchronizingcontrol ceives the full volume of t 18F. When the synchronizing control ISF'- is moved into position 187G, the resistance between 18G and 18L is decreased to thel minimum. The electric ick-.up IOL e circuit, while the electric pick-.up 10B. is faded out.

In the modied form as shown in Fig. 6, the transformer 27 having a secondary circuit 27B, the current passes through totermetallic sound as v and the -27,' (see Fig. 5),v

the secondaryl vsound pr minal 28 to 'wire 29 to terminal. 30 to. lead over 31 to terminal 32, through wirey 33,

to terminal 44, through wire 45 to thefelectric pick-uplOR, through wire 46 to terminal 18R and the resistance 18C, through the synchronizing control arm 18A and 18 t lrough the wire 47 to 'the' terminal 35,

through wire. 48 to the terminal 49, through the resistance 50 to the volume control 51', through the wire 52 tothe terminal 38 to the wire 39 tothe secondary coil, 2713i When the synchronizingcontrol arm 18A is moved to the left-or close `to the terminalflSL the i resistance` increases between arm 18A and terminal 18B. The current will divert 'at terminal 44 .through wire 45 tothe electric pick-u 10L, through the wire 53 to terminal 18L, t ence to arm 18A. e

In this modified circuit, in case one or the other ofthe electricpick-.ups 10B and 10L the synchronizing. control is to be tuned out without tuningr rthe other i trol 51l ismoved toward 'circuit passes from terminal .32 through wire '55 to terminal 54, thence to 51. 'cuit then continues as described in ous paragraph. I

The scratch filter 56 is 'so arranged in@4 i 5 and 6- between lterminals 18L and Fi 18 that it cushions the resistance as it in-v .creases and 'decreases between said terminals synchronizing control arm 18A,

which allows the current to' be increased in one pick-up unit and decreased in theA other pick-up unit uniformly without any `interruption or vibration which lbrings a uniin or lowering the volume, the volume con-y the terminal 54, the.

formly fading volume of music and simul- Y taneous increasing volume of music.

lI claim: 1. In an electric record having-two record turn-tab es, two oscillattone arm" an'd suitable electric sound transand, opening means operated by the oscillating movement ofthe tone arms for starting' y and stopping. the corresponding motors an electric circuit operatively connecting' both rglizk-ups, means 1n `said circult for.. controlg current selectivel ups andl simultaneou y increasing vcurrent througlh one while increasing current through.' v

produce sound from the 'ot er to electrically either recordv as desired. 2. The .structure specified in claim 1, and

pick-up circuits, and a rotary control engafmg said resistance and arran 'ed `to vary eueing means. A The structure specified in claim'l, in which saidi motor starting and `sto ping means comprises for each tone arm, a IJnge laying machine 4 yable tone arms, an electric pick-up on each mitting means to a tone chamber; an electric motor for each turn-table circuit closing.

current to the through said pick-'l v volume control means incorporated in 'said comprising a resistance coil l fixed on the tone arm, a V-shaped oscillatable switch arm arranged in the path of the movement of said finger, one arm of said switch adapted to "be engaged and swung by said finger to a fixed circuit closing contact to start the motor, the other arm of said switch as arranged to be engaged and moved by said finger when the tone arm is swung in the opposite 'direction, to open said circuit. l"

4. The structure specified in claim 1, and a scratch filter incorporated in said pick-up circuit.

5. The structure speciied in claim 1, in which said means for controlling the current to both pick-ups comprises a rheostat with one terminal connectedwwith one pick-up an the other terminal connected to the other pick-up, direct current transmitting means to said pick-ups, a synchronizing control arm operable on said rheostat between its terminals to selectively increase or decrease the current to the pick-ups, circuit wires from said control arm and a secondary resistance coil in said latter circuit comprising a volume control.

6. In an electric record-playing machine having two record turn-tables, a pair of electric pick-ups one each on a tone arm and operable on a record, a motor for each turntable, means iixed on each tone arm for closing circuit to the motor of its turntable when pick-up is moved to contacting 'position said electric circuit closing means being noncontacting with relation to each other when the pick-up is operatin over the tone producingarea of a recor 7. A music synchronizing attachment for phonographs with two record tables, corresponding tone armsz electric pick-ups2 an electric motors rotating said tables; said at- .tachment comprising a manually operated synchronizing control embodying a resistance coil in circuit with both pick-ups and a control lever arranged in circuit with said re'sistance'coil to adually increase current to one of said pic -ups and simultaneously decrease current to the other pickup to res ectively increase the volume of sound prouced by the first pick-up from the recor it is in contact with, and to decrease the volume of sound produced by up from4 its record, and a control synchronizingl control. means and the tone chamber of t e phonograph.

In testimony whereof I aix my signature.

FREDERIC H. STROM.

the other pickfor volume -of sound arranged in circuit between said 

